Plex on smart TV?

I've been using Plex through my Roku. Plex Media Server is installed on my desktop. I decided to purchase a Vizio Smart TV. It offers Netflix and a few other streaming services. Can I add Plex to the TV, or do I still need the Roku?

I guess this isn't the best place to ask, but what did you mean by "much worse" regarding DLNA? Not knowing anything about this, I googled DNLA Vizio and found a testimonial from someone who figured out how to do this and seems very pleased...